Fireproof fabric and method of making the same



radiated T15, 1931 cano s) HU'UiiCWb-lh PATENT OFFICE CAMILLE DREYFUS,OF NEW YORK, N. Y.,

AND HERBERT PLATT, OF CUMBERLAND,

, MARYLAND, ASSIGNORS TO GELANESE CORPORATION OF AMERICA, A CORPORATIONOF DELAWARE rmnrnoor Fume AND mnrnonor MAKING THE No Drawing.

This invention relates to the treatment of combustible material such asyarns and fabrics. of all kinds, paper or wood, etc. but particularly tothe treatment of yarns or fabrics composed in part or in whole oforganic derivatives of cellulose, in order to render the same fireproof-or flame proof.

An object of our invention is to produce a fabric or yarn which is fireproof or flame proof.

Afurther object of our inventlon 1s to render combustible material suchas paper,

I wood or fabrics of allkinds, but particularly fabrics composed inwhole or in part of organic derivatives of cellulose, 'fire proof bysubjecting the same to a solution containin phosphoric acid orequivalentacids.

Further objects of our invention will appear from the followin detaileddescription.

This invention is 0 general application, and may be used in therenderingflame-proof or fire-proof of combustible material of all kinds,such as paper and wood, but more articularly yarns or fabrics made ofall kin s of fibers such as cotton, reconstituted cotton,

natural silk and derivatives of cellulose. However, 1n the treatment 1naccordance with our invention of yarns or fabrlcs made of or ganicderivatives of cellulose, such great en hancement of fire-proof orflameroof qualities are attained, that we shall escribe our inventionwith respect to the treatment of such fabrics or yarns.

The organic derivatives of cellulose may be "organic esters ofcellulose, or'organic ethers of cellulose. Examples of organic esters ofcellulose are, cellulose formate, cellulose acetate, cellulosepropionate, and cellulose butyrate. Examples of organic ethers ofcellulose are methyl cellulose, ethyl cellulose and benzyl cellulose.may be composed entirely of one of the above mentioned organicderivatives of cellulose or it may be composed entirely of a mixture oftwo or more of the above named materials.

The fabric or yarn treated Application filed August 29, 1927., SerialNo. 216,332

Further, the fabric may be a mixed fabric composed of a mixture of yarnsmadeof any of the thermoplastic or organic derivatives of celluloseabove mentioned and of yarn made of other fibers. Likewise, the yarn tobe treated may be composed of a mixture of thermoplastic or organicderivatives of cellulose filaments and of other fibers. Examples of suchmixed fabrics oryarns are mixed cellulose acetate and natural silk,mixed cel- 5 lulose acetate and wool, mixed cellulose acetate andcotton, etc.

In the interest of brevity, a detailed descrlption will be given withrespect to a fabric composed entirely of cellulose acetate. 00

However, it is to be understood that this invention is not limited tothe treatment of pure cellulose acetate fabrics but may be apphed to anyyarn or fabric as set forth above.

According to our invention, the cellulose 5 acetate fabric treated witha solution containing phosphoric acid that is adapted to decrease itscombustibility. We have found for instance the ordinary phosphoric acidforinstance the ordinary phosphoric acid In\ one mode of carrying outour invention,

cellulose acetate fabric is immersed in an aqueous bath containing from50 to 150 grams of phosphoricacid per liter of solution. A bathcontaining 100 grams of phosphoric acid per liter of solution was foundto give very satisfactory results.

The temperature of he bath may be anywhere between ordinary roomtemperature (15 C.), to 60 C., although We -have found a bathtemperature of 40 C. is advantageous.

Moreover, the treating solution .may 75 The bath temperature is 40 C.and the time of immersion one hour. Obviously the concentration of thephosphoric acid, the temperature ofthe bath and the time of treatmentmay be varied within the wide limits set forth in the foregoing example.Likewise a salt other than thebasic aluminum acetate may used and thebath may contain 10 grams, 20 grams, grams, 40 grams, etc., of the salt.

This treatment of a cellulose acetate fabric results in a remarkableenhancement of its fire resistant properties. The cellulose aceta-tefabric treated in accordance with our invention will not flame. Thuswhen such fabric is heated to above the i ition point of untreatedcellulose acetate fabric by the application, for instance, of a nakedflame, I the fabric will not flame,the material simply melting withoutbursting into flame. The

results obtained by the treatment in accordance with the foregoingprocess are quite surprising, in thatthe fact that the use of an acidsuch as phosphoric acid gives these excellent results, is quiteunexpected, Moreover, the fabric, after treatment witli'ifihe fireproofin agent, retains its original excellent han 1e and 'fineappearance, whereas with the old methods of fire proofing either theappearance of the fabric is altered or the fabric is stiffenedmaterially. Apparently, the phosphoric acid combines with the fabric andeven after drastic washing of a fabric treated in accordance with ourinvention, the flame-proof properties of the fabric is not materlallydiminished.

As was stated before, other combustible materials can be treated inaccordance with our invention. Thus articles of wood and paper may berendered flame-proof by the use of our process. Fabrics or yards of theanimal orjegetable fibers such as silk, cotton, wool, linen, etc. may beflame-proofed in this manner. In the treatment of yarns, the yarns maybe subjected to the action of the flameproofing agent whilein the formof hanks, cops, bobbins, etcf The material may be treated with thesolution either by immersion therein or by otherwise applying the samesuch as by brushing, spraying, etc. Also the flame-proofing reagent maybe appliedto the tailed description is given merely by way ofillustration and that many variations may be made therein withoutdeparting from the spirit of our invention.

Having descr1bed our invention what we claim and desire to secure byLetters Patent is:

1. A fire proof of flame proof article made of normally combustiblematerial rendered fire proof or flame proof by the treatment with areagent containing a phosphoric acid in a free state.

2; A flame proof textile material such as yarn and fabric, made ofnormall combustible material rendered fire proo or flame proof by thetreatment with a reagent containing a phosphoric acid in a free state.

'3. A flame proof fabric containing yarn of normally combustiblematerial rendered fire proof by the treatment with a reagent containinga phosphoric acidrin a free state.

4. A fabric containing yarn of organic derivatives of. celluloserendered flame proof by treatment with a solution containing phosphoricacid in a free state.

5. A fabric containing yarn' of cellulose acetate rendered flame proofby treatment with a solution containing a substantial amount ofphosphoric acid.

-6. A fabric containing yarn of cellulose acetate rendered flame proofby treatment with a solution containing a substantial anliount ofphosphoric acid and an inorganic sa t.

7. The method of rendering flame proof or fire proof of articlescontaining normally combustible material comprising treating the samewith a reagent containing a phosphoric acid in a free state.

8. Method of rendering flame roof of a textile material such as yarn andabric containing normally combustible material comprising treating thesame with a reagent contairing a substantial amount of a phosphoric aci9. Method of treating fabrics containing yarn of organic derivatives ofcellulose comprising treating the same with a solution containinga'phosphoric acid in a free state.

10. Method oftreating fabrics containing yarn of cellulose acetatecomprising treating the same with a solution containing a phosv phoricacid in a'free state.

11. Method of treating fabrics containing yarn of cellulose acetatecomprising treating the same with a solution containing the phos- Iphoric acid aP ln as material to be tre ted in the form of a pasteMethmi. "eating fabrics nmining 130 THAllllhEMT a cases or TEX-tatsvluvvv lflkl hillbi luh "act: a

, 5 of approximately C. and for a period of approximately 15 minutes.

In testimony whereof, we have hereunto subscribed our names.

OAMILLE DREYFUS. HERBERT PLATT.

CERTIFICATE OF coRREcTIoNt Patent No. 1,837,150. Granted Decemberl5,1931, to

CAMYILVLE muarru's ET t.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiringjcorrection as follows: Page 1,line 69, strike out the words "for instance the ordinary" and-insert thewordsthat an aqueous solution of a; page 2, line 80, claim 1, vfor "of"read or; and that the said Letters Patent should be read with thesecorrections therein that the same.. may conform to the record of thecase in the Patent Office.

Signed and sealed this 9th day of'February, a. D. 1932.

M. J. Moore,

(Seal) Acting Commissioner of Patents.

Wlllllllllltlil.

